LeetCode - Subtree of Another Tree
Given two non-empty binary trees s and t, check whether tree t has exactly the same structure and node values with a subtree of s. A subtree of s is a tree consists of a node in s and all of this node's descendants. The tree s could also be considered as a subtree of itself. Example 1: Given tree s: 3 / \ 4 5 / \ 1 2 Given tree t: 4 / \ 1 2 Return true, because t has the same structure and node values with a subtree of s. Example 2: Given tree s: 3 / \ 4 5 / \ 1 2 / 0 Given tree t: 4 / \ 1 2 Return false.
还是用到了递归和序列化的解法:
/** * Definition for a binary tree node. * public class TreeNode { * int val; * TreeNode left; * TreeNode right; * TreeNode(int x) { val = x; } * } */ class Solution { public boolean isSubtree(TreeNode s, TreeNode t) { String str1 = serialize(s); String str2 = serialize(t); return str1.contains(str2); } private String serialize (TreeNode root){ if(root == null){return "#";} String serial = "<"+root.val+">"+ serialize(root.left) + serialize (root.right); return serial; } }
posted on 2018-09-26 11:01 IncredibleThings 阅读(129) 评论(0) 编辑 收藏 举报